In recent years, among various contact lenses, the demand for, in particular, contact lenses which can be continuously worn in eyes for a long period of time has become strong, so the development of various lenses has been proceeded.
As to the above contact lens which can be continuously worn in eyes for a long period of time, it is known that excellent affinity of lens materials for ocular tissues, in particular, cornea tissues is important, in addition to the importance of excellent oxygen permeability. Accordingly, there have been carried out various researches in a contact lens which has high oxygen permeability and shows stably excellent affinity for ocular tissues for a long period of time. However, a contact lens satisfying the above properties has not been provided yet.
In addition, lipid in lacrimal fluid easily adheres to, in particular, a water-absorptive contact lens, so there is a possibility that wearing comfort and transparency of the lens are lowered. Accordingly, it is desired that the lens is excellent in deposit resistance such as lipid-deposit resistance.
As a non-water-absorptive contact lens having a water content of at most about 5% by weight, conventionally, there has been widely spread a contact lens comprising a copolymer prepared by polymerizing, as a main component, a (meth)acrylate monomer or a silicon-containing monomer.
However, because such non-water-absorptive contact lens is substantially hydrophobic, the lens has defects that hydrophilic property of its surface is bad, its affinity for lacrimal fluid is poor and its wearing comfort is bad.
The present invention has been accomplished in consideration of the above prior art, and aims at providing a process for easily producing a contact lens which has high oxygen permeability and of which surface shows stably excellent hydrophilic property for a long period of time, and which is excellent in deposit resistance such as lipid-deposit resistance, and providing a contact lens having a hydrophilic surface, which is produced by the process.